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Performance
The data used in the metrics is that of what would be considered a fairly standard application in MongoDB that Mongoid could manage.
- 1,000,000 documents in the main collection
- 10,000 embedded documents on a root document (1-n)
- 10,000 embedded documents on a root document (1-1)
- 100,000 referenced documents to another collection (1-n)
- 100,000 referenced documents to another collection (1-1)
- 10,000 referenced documents to another collection (n-n)
* Performance metrics done on a 2.93 GHz i7 iMac / 8GB RAM, OSX 10.7, Mongoid 2.2.0
* The script to run the performance metrics can be found here.
Notes
Many to many relations are not recommended for over 10,000 documents when using MRI due to the garbage collector taking over 90% of the run time when calling #build or #create. This is due to the large array appending occuring in these operations.
 |
When performing appends to one to many relations we execute in batch (appending all at once instead of one at a time) due to the slow performance of MongoDB's $push atomic operator. |
| Operation | Time | Ops/sec |
|---|---|---|
| root (1,000,000 operations) | ||
Model#create |
417.93 | 2,392 |
Model#all.each |
40.87 | 24,476 |
Model#find |
0.001 | |
Model#save |
487.93 | 2,049 |
Model#update_attribute |
339.54 | 2,945 |
| embedded 1-n (10,000 operations) | ||
relation#build |
2.253 | 4,438 |
relation#clear |
1.230 | 8,130 |
relation#create |
4.899 | 2,041 |
relation#count |
0.011 | |
relation#delete_all |
1.377 | 7,262 |
relation#push (batch) |
3.496 | 2,860 |
relation#each |
0.027 | 370,370 |
relation#find |
0.044 | |
relation#delete |
0.045 | |
| embedded 1-1 (10,000 operations) | ||
relation#= |
3.902 | 2,562 |
| relational 1-n (100,000 operations) | ||
relation#build |
18.521 | 5,399 |
relation#clear |
4.085 | 24,479 |
relation#create |
45.464 | 2,199 |
relation#count |
0.051 | |
relation#delete_all |
5.596 | 17,869 |
relation#push (batch) |
34.551 | 2,894 |
relation#each |
0.055 | 1,818,181 |
relation#find |
0.020 | |
relation#delete |
0.410 | |
| relational 1-1 (100,000 operations) | ||
relation#= |
54.991 | 1,818 |
| relational n-n (10,000 operations) | ||
relation#build |
1.325 | 7,547 |
relation#clear |
0.350 | 28,571 |
relation#count |
0.001 | |
relation#delete_all |
0.001 | 10,000,000 |
relation#push (batch) |
2.628 | 3,805 |
relation#each |
0.005 | 2,000,000 |
relation#find |
0.010 | |
relation#delete |
0.060 | |
| eager loading 1-1 (10,000 docs) | ||
Model#each (without eager load) |
5.617 | 1,780 |
Model#includes (with eager load) |
2.966 | 3,371 |
| eager loading 1-n (10,000 docs) | ||
Model.all#each (without eager load) |
4.300 | 2,325 |
Model#includes (with eager load) |
2.094 | 4,775 |